Multiple brown tumors of the ribs simulating malignancy

Area of Science:

• Endocrinology
• Oncology
• Pathology

Background:

• Primary hyperparathyroidism is usually diagnosed early, making severe bone complications like osteitis fibrosa cystica rare.
• Asymptomatic hypercalcemia is the common presentation, preventing advanced disease manifestations.

Observation:

• A patient presented with multiple pleural-based masses and hypercalcemia, initially suggesting malignancy.
• The clinical presentation prompted an investigation into the cause of hypercalcemia and masses.

Findings:

• Histological and laboratory data confirmed the presence of brown tumors in the ribs.
• These findings were consistent with severe, undiagnosed primary hyperparathyroidism.

Implications:

• This case underscores the importance of considering metabolic bone disease in patients with unexplained hypercalcemia and masses.
• Rare presentations of primary hyperparathyroidism, such as brown tumors, should be recognized to avoid misdiagnosis, particularly of malignancy.